Patent GB-122886-A (GB)
Title: Improvements in Typewriting Machines for Coding and Decoding Messages.
Inventor: GRANT JOHN CAMERON
IPC: G09C3/00
Filed: 1918-02-04
Abstract: 122,886. Grant, J. C. Feb. 4, 1918. Machines with two sets of types for coding and decoding. -A typewriter for printing code and original messages simultaneously is provided with two distinct sets of typewheels or shuttles which receive equal angular and equal axial movements at each key operation, one set being non- adjustable and the other set being adjustable in accordance with a code number. The adjustable type-wheels may be formed with a number of splines or castellations for engaging splines or castellations on the shaft. In the arrangement shown, anvils H, H<2> on a shaft C carry a set of four adjustable shuttles B<1> - - B<4> and a single non-adjustable shuttle A respectively. The shuttle A is provided with four rows of types arranged with like letters superposed. The shuttles B<1> - - B<4> have each one row of types with nine or more letters repeated at the ends to provide a sufficient range for the code. Before coding or decoding, the anvils are detached and the shuttles B<1> - - B<4> are set relatively forwards or backwards in accordance with the code number, and are then secured together and again coupled to the stop arm D of the action. Each of the shuttles is formed with a number of lettered or numbered holes b<2>, Fig. 3, for engaging a fork which secures the shuttles together. The stop arm D is formed with a finger d' which can engage one of a series of notches b<1> on each of the shuttles B<1> - - B<4> The finger d<1> engages also a single notch in the shuttle A. In a modification, the non-adjustable shuttle is mounted in a stationary anvil and bears only one row of type. The shaft C is moved axially at each key-operation in order to bring the shuttles B<1> - - B<4> successively into printing position. For this purpose, the shaft is supported by a cam W, Fig. 8, adapted to raise and then drop the shaft. The cam is provided with a ratchetwheel T engaging a detent Z and an operating pawl S on the shift-lever L<1>. The character-key levers may operate a universal bar on the lever L'. According to the Provisional Specification, the type-members may be successively moved into position by a spring or weight or by compressed air, a bell or buzzer being provided for indicating when the code figure has been completed; further, the type-wheels may be locked by a nut engaging a bayonet thread on the shaft. Sheet feeding and guiding arrangements; hammer-impression arrangements; ink-ribbon mechanism.-The coded and original messages are printed on the same sheet P, Fig. 1. which passes from rollers F', F<2> to feed-rollers F<3>, F<4> and is looped round a roller F<5>, arranged so that sufficient space is provided between the messages. The impression-hammer is formed with two striking-faces g<1>, g<2>. A horizontally arranged ink-ribbon may be provided for each set of type-wheels; or a single vertical ribbon may serve for both sets. Where a vertical ribbon is provided, the usual key for depressing the type-shuttles to render the writing visible may be arranged also to displace the ribbon laterally.